title: Debrisoquine and S-mephenytoin hydroxylation polymorphisms in a Russian population living in Estonia.
abstract: OBJECTIVE
  To investigate the CYP2D6 and CYP2C19 phenotypes and genotypes in a Russian population of Estonia.
  
  
  METHODS
  Two hundred and eighteen unrelated healthy subjects of Russian origin were studied. All participants took 10 mg debrisoquine and 100 mg S/R-mephenytoin for phenotyping. The CYP2D6 genotype was analysed by PCR amplification for the CYP2D6*3 and CYP2D6*4 alleles and subjects with S/R-mephenytoin ratios of greater than 0.5 were genotyped with respect to CYP2C19*2 and CYP2C19*3 alleles.
  
  
  RESULTS
  Seventeen subjects (7.8%) were classified as poor metabolisers of debrisoquine and 5 (2.3%) as poor metabolisers of S-mephenytoin. The frequency of CYP2D6*4 was 14.4% and that of CYP2D6*3 1.4%. Seven of 15 poor metabolisers of debrisoquine (47%) carried two defective CYP2D6 alleles (CYP2D6*3 or CYP2D6*4). Six of the 10 S-mephenytoin poor-metaboliser alleles (60%) carried either the CYP2C19*2 or CYP2C19*3.
  
  
  CONCLUSIONS
  The frequencies of poor metabolisers of debrisoquine and S-mephenytoin among Russians were similar to those in other Caucasian populations. The CYP2D6 poor-metaboliser phenotype was predicted by PCR-based amplification for the CYP2D6*3 and CYP2D6*4 alleles with 47% accuracy. The frequency of the CYP2D6*4 allele was lower in Russians than in other Caucasian populations studied so far.
authors.affiliation: Department of Pharmacology, University of Tartu, Estonia.
authors.forename: T
authors.initials: T
authors.lastname: Marandi
authors.forename: M L
authors.initials: ML
authors.lastname: Dahl
authors.forename: L
authors.initials: L
authors.lastname: Rägo
authors.forename: R
authors.initials: R
authors.lastname: Kiivet
authors.forename: F
authors.initials: F
authors.lastname: Sjöqvist
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001189:Aryl Hydrocarbon Hydroxylases; D065731:Cytochrome P-450 CYP2C19; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D003647:Debrisoquin / Q000378:metabolism*; D005260:Female; D005838:Genotype; D006801:Humans; D006900:Hydroxylation; D008297:Male; D008617:Mephenytoin / Q000378:metabolism*; D008875:Middle Aged; D006899:Mixed Function Oxygenases / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic
chemical_list: D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D019389:Cytochrome P-450 CYP2D6; D008617:Mephenytoin; D003647:Debrisoquin